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PubMed2004

Prognostic factors in differentiated thyroid carcinomas and their implications for current staging classifications.

Differentiated thyroid carcinomas (DTC) (papillary, follicular and follicular type of papillary) have a favourable prognosis, but a proportion of patients develop recurrences and eventually die of the disease. Various prognostic factors have been identified and been used to create the current staging classifications (AGES, AMES, MACIS, EORTC, UICC-TNM). We examined 499 DTC patients retrospectively to validate known prognostic factors that enable them to be recognised as having either a low or a high risk of death related to a recurrence of DTC, by reference to the current staging classifications. Sixty-nine of them (14%) had local or distant recurrences, the mean time to recurrence being 7.7 years. The 10-year disease-free survival rate was 80%, and the ten-year overall survival rate for the entire group was 91%, with a mean survival time of 8.7 years. Male gender, a follicular type of tumour, larger tumour size, extrathyroidal invasion outside the capsule and nodal metastases were all related to a higher incidence of tumour recurrence, and the follicular type of histology, age > 45 years, larger tumour size and local invasion entailed poorer survival. The AMES and to some extent the EORTC classification were not reproducible in this material, mainly because some prognostic variants were no longer encountered or were insufficient in number to allow reliable conclusions to be drawn. The MACIS staging classification leaves the definition of the intermediate and high risk groups too wide and is therefore not very reliable. Pooling of stages I and II improved the relevance of the TNM classification. All the current staging classifications are able to discern a low risk DTC group well. We achieved a highly accurate definition of risk in the present material using only two parameters, age (cut-off value 50 years) and extracapsular invasion of the thyroid gland.

Adenocarcinoma, Follicular↗

PubMed2006

Cellular focal segmental glomerulosclerosis: Clinical and pathologic features.

Five pathologic variants of idiopathic focal segmental glomerulosclerosis (FSGS) are recognized: collapsing (COLL), cellular (CELL), glomerular tip lesion (GTL), perihilar, and not otherwise specified (NOS). The prognostic significance of CELL FSGS has not been determined. We compared the presenting clinical and pathologic characteristics in 225 patients with CELL (N=22), COLL (N=56), GTL (N=60), and NOS (N=87) variants of idiopathic FSGS. CELL, COLL, and tip lesion all showed greater frequency and severity of nephrotic syndrome, and shorter time to biopsy compared to NOS. Predictors of end-stage renal disease (ESRD) for all FSGS patients included initial serum creatinine, % global sclerosis, % COLL lesions, chronic tubulo-interstitial injury score, and lack of remission response. COLL FSGS had the highest rate of renal insufficiency at presentation, most extensive glomerular involvement and chronic tubulo-interstitial disease, fewest remissions (13.2%), and highest rate of ESRD (65.3%). GTL patients were older and showed the highest remission rate (75.8%) and lowest rate of ESRD (5.7%). CELL variant showed intermediate rates of remission (44.5%) and ESRD (27.8%) compared to COLL and tip lesion. CELL variant may include cases of unsampled tip or COLL lesion, underscoring the importance of adequate sampling. Our data support the view that CELL and COLL FSGS are not equivalent and validates an approach to pathologic classification that distinguishes between COLL, CELL, and tip lesion variants of FSGS.

Adolescent↗

PubMedDate not supplied

[Evaluation of the proliferation and line of lymphoid cells in various lymphoproliferative diseases using a double immunocytochemical method].

The increased range of the diagnostic criteria and the introduction of the classification scheme "Practical Formulation of Non-Hodgkin's Lymphomas for Clinical Application" made the authors to study proliferative potential of lymphoid cells with identification of the cell line affiliation. The investigation was carried out with the use of the double immunocytochemical test employing anti-nuclear (Ki-67) and line-specific monoclonal antibodies on peripheral blood lymphocytes, those of lymph nodes and bone marrow obtained from 40 patients with lymphoproliferative diseases and on the cells of lymphoblastoid line 501. The disease variant was classified according to the WHO criteria. The highest (> 60%) proliferative activity of lymphoid cells was found in the bone marrow in acute non-T non-B lymphoblast leukemia and in lymph node in T-cell and non-T non-B-cell lymphoblast lymphosarcoma. A broad range in the number of proliferative cells existed among B-cell lymphosarcomas of lymphoblast (12-73%) and prolymphocytic (0-91%) variants. Together with heterogeneous immunological phenotype, this reflects a wide spectrum of various nosological entities recognized by the WHO classification as lymphoblast and prolymphocytic variants of lymphosarcoma, says about the defects of the above classification. Extremely low (< 1%) percent of proliferative cells was observed in B-cell chronic lymphoid leukemia and hairy-cell leukemia. These differences in tumor cell proliferative potential in different lymphoproliferative diseases agree with the views on maturation and differentiation of lymphoid cells. The data obtained by the authors support the necessity of correcting routine histological data by immunological characteristics of pathological lymphoid cells, primarily, by introduction of data on cell proliferative activity.(ABSTRACT TRUNCATED AT 250 WORDS)

Cell Division↗

PubMed2002

Fine-needle aspiration biopsy of anaplastic large cell lymphoma, small cell variant with prominent plasmacytoid features: case report.

Anaplastic large cell lymphoma (ALCL), according to the new WHO classification, is a diagnosis limited to T/NK cell lymphomas. We present a case that demonstrates a new morphologic variant of ALCL with significant possible pitfalls for the cytopathologist. A fine-needle aspiration biopsy of a cervical lymph node showed a cellular aspiration comprised of medium-sized plasmacytoid cells in a discohesive and focally loosely cohesive pattern. The cytologic diagnosis confirmed the presence of malignancy and noted the prominent plasmacytoid features. An accompanying comment favored melanoma and included a broad differential. No cell block was available for immunohistochemical stains. Immunophenotyping of the subsequent excisional node biopsy showed an anaplastic lymphoma kinase (ALK)-positive ALCL. This case illustrates a new variant of ALCL. Although ALCL variants, such as small cell and lymphohistiocytic, are well recognized, the plasmacytoid features are an additional potential source for misdiagnosis. This case report shows that a cytopathologist should include ALK-positive ALCL in the differential diagnosis of plasmacytoid proliferations cell because of the clinical importance of the ALK-positive ALCL.

Biomarkers, Tumor↗

PubMed2002

Dorsal bony septum: a split cord malformation variant.

Split cord malformations (SCMs) are rare spinal anomalies and their classification is still a matter of debate. There is no widespread consensus on the embryological basis of this entity. The unified theory, proposed by Pang et al. [Neurosurgery 1992;31:451-480], was an attempt to explain the embryogenetic mechanism as a basic error occurring around the time when the primitive neuroenteric canal closes. We report two unusual cases of SCMs with a dorsally situated bony spur. We analyzed the radiological, clinical and surgical features of the lesions and were not able to classify these cases according to the unified theory. Further embryological studies should be conducted to elucidate the mechanisms of occurrence of these lesions, and the dorsal bony septum variant should be considered in SCM surgery.

Child↗

PubMed2004

Effects of different experimental conditions on the PrPSc core generated by protease digestion: implications for strain typing and molecular classification of CJD.

The discovery of molecular subtypes of the pathological prion protein PrPSc has provided the basis for a novel classification of human transmissible spongiform encephalopathies (TSEs) and a potentially powerful method for strain typing. However, there is still a significant disparity regarding the understanding and nomenclature of PrPSc types. In addition, it is still unknown whether a specific PrPSc type is associated with each TSE phenotypic variant. In sporadic Creutzfeldt-Jakob disease (sCJD), five disease phenotypes are known, but only two major types of PrPSc, types 1 and 2, have been consistently reproduced. We further analyzed PrPSc properties in sCJD and variant CJD using a high resolution gel electrophoresis system and varying experimental conditions. We found that pH varies among CJD brain homogenates in standard buffers, thereby influencing the characteristics of protease-treated PrPSc. We also show that PrPSc type 1 and type 2 are heterogeneous species which can be further distinguished into five molecular subtypes that fit the current histopathological classification of sCJD variants. Our results shed light on previous disparities in PrPSc typing, provide a refined classification of human PrPSc types, and support the notion that the pathological TSE phenotype is related to PrPSc structure.

Animals↗

PubMed1998

Dominant expression of sex-hormone-binding-globulin exon-7 splicing variant over wild-type mRNA in human ovarian cancers.

The intracellular expression of sex-hormone-binding-globulin(SHBG) exon-7-splicing-variant mRNA in human ovarian cancers was demonstrated by reverse-transcription/polymerase-chain-reaction, Southern-blot and DNA-sequencing analyses. Analysis of the missing base pairs proved that they corresponded to the entire exon 7, which is considered to encode a portion of the steroid-binding site, suggesting that the steroid-binding affinity of this variant might be different from that of the SHBG wild type. SHBG wild-type and variant mRNA was detected in all normal ovaries and in benign and malignant ovarian tumors analyzed. There were no significant differences in mean SHBG wild-type and variant mRNA levels among the 3 types of tissue, but the ratio of SHBG exon-7-splicing-variant to wild-type mRNA level in ovarian cancers was significantly higher (p < 0.05) than that in normal ovaries, with over-expression in some benign tumors. SHBG mRNA levels and the ratio of SHBG variant to wild-type mRNA was not associated with histological classification or clinical stages of ovarian cancers. These results suggest that over-expression of SHBG-exon 7-splicing-variant mRNA to the wild type might indicate the potential for neoplastic transformation.

Blotting, Southern↗

PubMed1997

The Heidelberg classification of renal cell tumours.

This paper presents the conclusions of a workshop entitled 'Impact of Molecular Genetics on the Classification of Renal Cell Tumours', which was held in Heidelberg in October 1996. The focus on 'renal cell tumours' excludes any discussion of Wilms' tumour and its variants, or of tumours metastatic to the kidneys. The proposed classification subdivides renal cell tumours into benign and malignant parenchymal neoplasms and, where possible, limits each subcategory to the most commonly documented genetic abnormalities. Benign tumours are subclassified into metanephric adenoma and adenofibroma, papillary renal cell adenoma, and renal oncocytoma. Malignant tumours are subclassified into common or conventional renal cell carcinoma; papillary renal cell carcinoma; chromophobe renal cell carcinoma; collecting duct carcinoma, with medullary carcinoma of the kidney; and renal cell carcinoma, unclassified. This classification is based on current genetic knowledge, correlates with recognizable histological findings, and is applicable to routine diagnostic practice.

Humans↗

PubMed2026

Cytogenetic Diversity of Variant Philadelphia Translocations in Chronic Myeloid Leukemia.

INTRODUCTION: Chronic myeloid leukemia (CML) is a disease characterized by Philadelphia (Ph) translocations. These translocations can be classical or variant. The structural features and diagnostic implications of variant Philadelphia translocations remain incompletely defined, and they display considerable cytogenetic heterogeneity. METHODS: In this retrospective study, variant Ph translocations identified by conventional cytogenetic analysis and fluorescence in situ hybridization (FISH) were systematically classified among 639 patients diagnosed with CML. A total of 35 patients with variant Ph translocations were included in the analysis. Molecular follow-up data, when available, were assessed using RT-qPCR analyses in a subset of patients. RESULTS: Chromosome analysis revealed 2 simple and 33 complex variant Ph translocations. FISH analysis, performed in 20 patients, identified deletions involving BCR, ABL1, or both in a limited number of cases. Additional chromosomal abnormalities and secondary translocations accompanied variant Ph translocations in four patients. The partner chromosomes involved in variant Ph translocations showed marked diversity, involving multiple chromosomal loci. CONCLUSION: Variant Philadelphia chromosome translocations in CML exhibit substantial cytogenetic diversity, reflecting the complexity of their underlying genomic architecture. The rarity and heterogeneity of these rearrangements complicate their classification and interpretation in routine diagnostic practice. Descriptive reporting of variant Ph translocations may contribute to a better understanding of their diagnostic complexity and support more accurate cytogenetic interpretation in CML.

Humans↗

PubMed2026

Mitochondrial DNA diversity in Ecuadorian populations: Recurrence of variant 16136 within haplogroup B2.

The identification of lineage-defining variants, frequently found in the coding region of mitochondrial DNA (mtDNA), is essential for refining haplogroup classification. Most mtDNA studies in South American populations have focused on the control region (CR), which has provided important insights into population structure and maternal lineage origins, although information needed for more robust phylogenetic resolution has been neglected. This study investigates the maternal genetic structure of Ecuadorian populations by combining CR and whole mitogenome analyses. Sequences from the mtDNA CR were obtained from 461 individuals (253 Mestizos and 208 Native Americans), while complete mitogenomes were sequenced for 127 individuals to improve phylogenetic resolution by identifying lineage-defining variants present in coding region. Most mtDNA haplogroups in the two population groups analyzed were of Native American origin (A2, B2, B4, C1, D1, D4), with significant differences in the distribution of specific lineages between them. Among Mestizos, African haplogroups (all within the L branches) and Eurasian haplogroups (H, K, R, U) were detected at low frequencies, whereas no African lineages were observed among Native Americans. The results obtained highlighted a heterogeneity within Ecuadorian populations that must be considered when developing mtDNA haplotype databases for forensic purposes. Whole mitogenome sequences enabled the identification of variants that refined haplogroup classifications, provided a more accurate reconstruction of the maternal genetic diversity, and improve the discrimination between Native American and Asian maternal lineages within haplogroup B4b.

Humans↗

PubMed2026

Biallelic pathogenic variants in FLNB are associated with paediatric steroid-resistant nephrotic syndrome via podocyte cytoskeletal dysfunction.

BACKGROUND: Steroid-resistant nephrotic syndrome (SRNS) is a severe paediatric kidney disease and a leading cause of end-stage kidney disease in children, with a high genetic contribution. While over 80 monogenic causes of SRNS have been identified, a significant proportion of affected patients still lack a clear genetic diagnosis, indicating that additional causative genes remain to be discovered. METHODS: Through whole-exome sequencing of a paediatric SRNS cohort, we identified three probands carrying biallelic FLNB pathogenic variants. Sanger sequencing was performed for familial cosegregation verification and ACMG classification. Expression of Filamin B, Nephrin and Synaptopodin in renal tissues was assessed by immunohistochemistry/immunofluorescence. Wild-type and patient-derived variant FLNB plasmids were constructed and transfected into HEK293T cells and immortalised human podocytes (HPCs). The effects of these variants on protein expression, localisation and cytoskeletal organisation were assessed by western blotting and immunofluorescence. FLNB expression in HPCs was silenced using shRNA to evaluate the impact on podocyte marker proteins, cytoskeletal integrity and migratory capacity. A zebrafish flnb knockdown model was employed to validate its effects on renal development. RESULTS: All three probands presented with isolated SRNS without skeletal developmental abnormalities, and renal tissues showed significantly reduced Filamin B protein expression. In vitro, p.L117P and p.M1803L variants led to markedly reduced protein expression, while p.R470L and p.K2586R induced perinuclear aggregation of Filamin B accompanied by F-actin rearrangement. FLNB silencing led to downregulation of Nephrin and Synaptopodin, cytoskeletal disorganisation and impaired cell migration. Zebrafish flnb knockdown exhibited pericardial oedema, defective nephron development and abnormal podocyte foot processes. CONCLUSION: We report for the first time that biallelic FLNB pathogenic variants are associated with paediatric SRNS by disrupting Filamin B expression, cytoskeletal integrity and podocyte function, providing evidence that FLNB is a novel monogenic cause of SRNS.

Humans↗

PubMed1989

[Disseminated herpes zoster in chronic lymphatic leukemia].

A 73-year-old woman suffering from chronic lymphatic leukemia presented a rare variant of zoster with disseminated eruptions. Ultrastructural negative staining revealed viruses of the herpes group. Herpes simplex was excluded by means of fluorescence-labelled monoclonal antibodies (HSV-1/HSV-2 direct specimen identification/typing test). It is proposed that the conventional classification of zoster into a segmental and a generalized variant should be supplemented.

Aged↗

PubMed2003

Boosting bit rates and error detection for the classification of fast-paced motor commands based on single-trial EEG analysis.

Brain-computer interfaces (BCIs) involve two coupled adapting systems--the human subject and the computer. In developing our BCI, our goal was to minimize the need for subject training and to impose the major learning load on the computer. To this end, we use behavioral paradigms that exploit single-trial EEG potentials preceding voluntary finger movements. Here, we report recent results on the basic physiology of such premovement event-related potentials (ERP). 1) We predict the laterality of imminent left- versus right-hand finger movements in a natural keyboard typing condition and demonstrate that a single-trial classification based on the lateralized Bereitschaftspotential (BP) achieves good accuracies even at a pace as fast as 2 taps/s. Results for four out of eight subjects reached a peak information transfer rate of more than 15 b/min; the four other subjects reached 6-10 b/min. 2) We detect cerebral error potentials from single false-response trials in a forced-choice task, reflecting the subject's recognition of an erroneous response. Based on a specifically tailored classification procedure that limits the rate of false positives at, e.g., 2%, the algorithm manages to detect 85% of error trials in seven out of eight subjects. Thus, concatenating a primary single-trial BP-paradigm involving finger classification feedback with such secondary error detection could serve as an efficient online confirmation/correction tool for improvement of bit rates in a future BCI setting. As the present variant of the Berlin BCI is designed to achieve fast classifications in normally behaving subjects, it opens a new perspective for assistance of action control in time-critical behavioral contexts; the potential transfer to paralyzed patients will require further study.

Algorithms↗

PubMed1998

Comparison of professional judgment versus an algorithm for nutrition status classification.

OBJECTIVES: The classification of a patient's nutrition status is important for identifying patients who require nutrition care, for designing effective nutrition interventions, and for measuring severity of illness. The objective of this study was to evaluate the reliability and validity of two variants of the Department of Veterans Affairs' nutrition status classification: professional judgment versus an algorithm. METHODS: The study consisted of two phases, both of which included providing a sample of approximately 60 registered dietitians and 60 clinical dietetic technicians with data on 16 (phase I) and 20 (phase II) patients, to which they assigned nutrition statuses using both professional judgment and the algorithm. Improvements in instructions and training were implemented between the two phases. Interrater reliability of the responses was calculated, and content validity was measured by comparing the staff's responses with those of an expert panel. RESULTS: Reliability improved significantly between phases for both professional judgment and the algorithm. Greater reliability and validity were observed with use of the algorithm, by both dietitians and technicians, during both phases. CONCLUSION: Classification of a patient's nutrition status is important in the delivery of cost-effective health care. The Department of Veterans Affairs' nutrition status classification is a good one for assessing nutrition status quickly and reliably, especially when an algorithm is used. The results underscore the advantages of a classification system based on an algorithm when the system is designed to be used by many different staff across multiple facilities.

Adult↗

PubMed1993

Consensus conference on well-differentiated thyroid cancer: a summary.

OBJECTIVE: To update recommendations for the surgical treatment of well-differentiated thyroid cancer. DATA SOURCES: Literature reviews and personal files. STUDY SELECTION: Panelists selected relevant articles to make arguments for and against current recommendations for the surgical treatment of well-differentiated thyroid cancer. OUTCOMES: Four aspects of surgical treatment were considered: (a) the extent of surgical resection, (b) the definition and utilization of high- and low-risk patient groups, (c) who should perform thyroid surgery and (d) the use of radioactive iodine. RECOMMENDATIONS: Total thyroidectomy is not the treatment of choice for all well-differentiated thyroid cancers. The use of risk factors help select those patients in whom a total thyroidectomy would be of benefit. High-risk patients are those who are considered at high risk according to the AGES and AMES classifications or who have lymph-node metastases, aggressive variants of their disease, multifocal cancer or disease in the contralateral thyroid lobe and a history of radiation to the neck. Those at low-risk are those previously described as being at low risk according to the AGES and AMES classifications. General surgery training programs across Canada need to ensure that their residents obtain enough experience in thyroid surgery that as general surgeons they can perform this type of surgery with low morbidity. CONCLUSIONS: The findings of this consensus conference were supported by those of several review articles and by the arguments put forward by the panelists. These findings are only guidelines as to the surgical approach to well-differentiated thyroid cancer.

Age Factors↗

PubMed1987

[Psoriasis pustulosa generalisata--classification, clinical aspects and therapy. Review and experiences with 18 patients].

On the basis of clinico-morphological criteria we suggest the following classification of various pustular forms of psoriasis into four subtypes: generalized pustular psoriasis (von Zumbusch) and its atypical forms, erythema anulare centrifugum-like psoriasis with and without pustulation (EACP); psoriasis vulgaris with pustulation; palmo-plantar pustular psoriasis (Königsbeck-Barber) and its acral variant; acrodermatitis continua suppurativa (Hallopeau), and transitional forms. This classification takes into consideration both clinical aspects and response to treatment, and allows a prognosis of the various types of pustular psoriasis. Owing to its mild course and good treatment results, EACP represents a special form of psoriasis pustulosa generalisata. In our group of patients, systemic glucocorticosteroid therapy has proved deleterious, whereas oral photochemotherapy and etretinate have been found to be highly effective modes of therapy with only mild side effects and have been able to induce even permanent remission in EACP.

Adult↗

PubMed1993

Sertoli-Leydig cell tumors of the ovary: review with emphasis on historical aspects and unusual variants.

Among the many contributions to gynecological pathology of Dr. Robert Meyer were his observations on Sertoli-Leydig cell tumors and the formulation of a classification of them that is the basis of the one used today. Selected variants in this category of tumors are reviewed here. Sertoli cell tumors are of interest clinically because, in contrast to other tumors in this category, they tend to be estrogenic rather than androgenic. They are important for the pathologist to be aware of, because other neoplasms of diverse types may mimic them. Heterologous Sertoli-Leydig cell tumors are noteworthy; since they may feature mucinous epithelium, carcinoid, skeletal muscle, and/or cartilage, they may present a confusing histologic picture that could result in a misdiagnosis. Similarly, the recently recognized retiform variant of Sertoli-Leydig cell tumor is apt to be misdiagnosed because its pattern of slit-like glandular spaces and papillae is often confused with tumors in the common epithelial category. These retiform lesions are also less often androgenic than are other Sertoli-Leydig cell tumors. Finally, neoplasms with bizarre nuclei and tumors that occur in pregnancy, which often have prominent intercellular edema, are briefly discussed.

Adult↗

PubMed1981

[Characterization of genetic EEG-variations with the amplitude-interval-analysis. III. Assignment of new obtained EEGs to well-known types of bioelectric activities on the basis of data of amplitude-interval-analysis (author's transl)].

Quantitative description of some EEG-variants by amplitude-interval (time-domain) analysis revealed significant differences of parameter means but failed to give one single, sufficiently reliable criterion for classification. Therefore, we tried to solve the problem of classification through quantitative criteria by discriminant analysis. For each EEG, 128 different measurements were taken, but only 104 were included in the analysis; the rest failed to contribute any measurable information. For 243 of th 298 probands, the data were sufficient for inclusion in the study. Only 15 (6.2%) were classified falsely; this number was reduced to 3 (1.7%) when the calculation was performed leaving out the (64) controls. A control analysis by a Monte-Carlo-Method in which the classification criterium was calculated using 80% of all cases only, and the remaining 20% were then attributed tentatively to the variant groups, gave much less convincing results. It follows that more and better criteria for separation of these variants have to be developed before classification of EEGs exclusively on the basis of measurements will become possible.

Electroencephalography↗